Since the advent of artificial lighting man has been vexed by the problem of having to find his way to bed in the dark after turning out the light. Frequently he finds himself stumbling over or bumping into objects on the way and this poses a real hazard, especially for older people who might fall or incur serious bodily injury.
The same problem is experienced in a garage or carport when the light is turned off before getting into the car.
The problem is aggravated by the appreciably long period of time required for the eyes to adjust to the dark after having become accustomed to a lighted room.
A real need exists for a means for continuing the energization of a light for a period of time following the turning-off of a light switch circuit.